WO2024022537A1 - Ultrasonic welding head and ultrasonic welding apparatus - Google Patents

Abstract

An ultrasonic welding head and an ultrasonic welding apparatus. The ultrasonic welding head comprises a welding head body (1), a welding platform (2) and welding teeth (3), wherein the welding head body (1) comprises a first connecting surface (11); the welding platform (2) comprises a second connecting surface (22) and a bearing surface (21), which are arranged opposite each other, the first connecting surface (11) being connected to the second connecting surface (22), and the area of the second connecting surface (22) being less than that of the first connecting surface (11); and the welding teeth (3) are arranged on the bearing surface (21).

Description

Ultrasonic welding head and ultrasonic welding equipment

This application claims priority to the Chinese patent application with application number 202321701631.7, which was submitted to the China Patent Office on June 30, 2023. The entire content of this application is incorporated into this application by reference.

Technical field

This application relates to the technical field of lithium battery manufacturing, for example, to an ultrasonic welding head and ultrasonic welding equipment.

Background technique

During the processing of lithium-ion batteries, ultrasonic welding is mostly used to weld the tabs and connecting pieces, and the tabs and current collectors. Ultrasonic welding uses high-frequency vibration waves to transmit to the surfaces of two objects to be welded. Under pressure, the surfaces of the two objects rub against each other to form fusion between the molecular layers. Ultrasonic welding equipment in the related art usually includes a welding head and welding teeth provided on the end face of the welding head. Since the welding teeth are directly provided on the end face of the welding head, the force during welding will directly act on the welding head. When the welding power is If it is too large, it will easily cause the welding head to break, and the welded finished product will easily crack. In addition, directly processing the welding teeth on the end face of the welding head will be difficult to process and the processing cost will be high.

Contents of the invention

This application provides an ultrasonic welding head and ultrasonic welding equipment, which can prevent the welding head from breaking when the welding power is too high, ensure the quality of the finished product, and reduce the processing difficulty and cost.

In a first aspect, embodiments of the present application provide an ultrasonic welding head, including:

The welding head body includes a first connection surface;

Soldering station, the soldering station includes a second connecting surface and a load-bearing surface arranged oppositely, the first connecting surface is connected to the second connecting surface, and the area of the second connecting surface is smaller than that of the first connecting surface. area;

Welding teeth are arranged on the bearing surface.

In one embodiment, the thickness H ₁ of the soldering station satisfies: 1.8mm≤H ₁ ≤2.5mm.

In one embodiment, the number of the welding teeth is multiple, and the plurality of welding teeth are arranged in an array on the bearing surface.

In one embodiment, a plurality of the welding teeth form a rectangular array, the length of the rectangular array is L ₂ , the width of the rectangular array is B ₂ , the length of the first connection surface is L ₁ , and the The width of the first connecting surface is B ₁ , where 1.6mm≤L ₁ -L ₂ ≤2.4mm and 1.6mm≤B ₁ -B ₂ ≤2.4mm.

In one embodiment, the welding teeth include oppositely arranged and concentric welding planes and a fixing plane, the fixing plane is connected to the bearing surface, the welding plane is arranged to be in contact with the parts to be welded, the welding plane The area is smaller than the area of the fixed plane.

In one embodiment, both the welding plane and the fixing plane are circular, and an arc-shaped surface transition is used between the welding plane and the fixing plane.

In one embodiment, the area of the welding plane is S ₁ and the area of the fixing plane is S ₂ , where 4/(95π)≤S ₁ /S ₂ ≤1/(2π).

In one embodiment, the welding tooth has a hemispherical structure, the diameter D of the fixed plane ranges from 1.2mm to 1.9mm, and the capping depth H ranges from _0.02mm to 0.1mm, so The area S ₁ of the welding plane ranges from 0.08mm ² to 0.6mm ² .

In one embodiment, both the welding plane and the fixing plane are polygonal, and the transition surface between the welding plane and the fixing plane includes at least one plane.

In one embodiment, the distance between the centers of two adjacent welding teeth is no more than 2 mm.

In one embodiment, the soldering station has a cylindrical structure or a platform structure.

In one embodiment, the soldering station has a cylindrical structure, a prism structure, a truncated cone structure or a prism structure.

In one embodiment, when the welding station has a cylindrical structure or a truncated cone structure, a rounded transition surface is provided between the top surface and the side surface of the welding station;

When the welding station has a prism structure or a pyramid structure, a rounded transition surface is provided between two adjacent side surfaces and between the top surface and the side surfaces of the welding platform.

In one embodiment, there are multiple soldering stations, a plurality of soldering stations are arranged in an array on the first connection surface, and at least one welding tooth is provided on each soldering station. .

In one embodiment, the first connection surface is provided on at least one side of the welding head body.

In a second aspect, embodiments of the present application provide ultrasonic welding equipment, including an ultrasonic generator, a transducer, a horn, and an ultrasonic welding head as described in any of the above solutions. The output end of the ultrasonic generator It is connected to the transducer, and the transducer is connected to the ultrasonic welding head through the horn.

Description of drawings

Figure 1 is a schematic structural diagram of an ultrasonic welding head provided by an embodiment of the present application;

Figure 2 is a schematic side view of an ultrasonic welding head provided by an embodiment of the present application;

Figure 3 is a schematic top view of an ultrasonic welding head provided by an embodiment of the present application;

Figure 4 is a partial structural schematic diagram of the ultrasonic welding head provided by the embodiment of the present application;

Figure 5 is a schematic diagram 2 of the partial structure of the ultrasonic welding head provided by the embodiment of the present application;

Figure 6 is a schematic diagram of the dimensions of the welding head body, welding station and welding teeth in the ultrasonic welding head provided by the embodiment of the present application;

Figure 7 is a schematic structural diagram of a welding tooth provided by an embodiment of the present application;

Figure 8 is a schematic structural diagram of the ultrasonic welding equipment provided by the embodiment of the present application.

in:

1-The welding head body; 11-The first connection surface;

2-soldering station; 21-bearing surface; 22-second connection surface;

3-Welding teeth; 31-Welding plane; 32-Fixed plane; 33-Arc surface;

4-Connection part;

5-ultrasonic generator; 51-transducer; 52-amplifier.

Implementation

In the description of this application, unless otherwise explicitly stipulated and limited, the terms "connected", "connected" and "fixed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral body. ; It can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be an internal connection between two elements or an interaction between two elements.

In this application, unless otherwise explicitly stated and limited, the term "above" or "below" a first feature on a second feature may include direct contact between the first and second features, or may also include the first and second features. Not in direct contact but through additional characteristic contact between them. Furthermore, the terms "above", "above" and "above" a first feature on a second feature include the first feature being directly above and diagonally above the second feature, or simply mean that the first feature is higher in level than the second feature. “Below”, “under” and “under” the first feature is the second feature includes the first feature being directly below and diagonally below the second feature, or simply means that the first feature is less horizontally than the second feature.

In the description of this embodiment, the terms "upper", "lower", "left", "right" and other orientations or positional relationships are based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplified operation. It is not intended to indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be construed as a limitation on the present application. In addition, the terms "first" and "second" are only used for descriptive purposes and have no special meaning.

This embodiment provides an ultrasonic welding equipment. Figure 8 is a schematic structural diagram of the ultrasonic welding equipment. The ultrasonic welding equipment includes an ultrasonic generator 5, a transducer 51, a horn 52 and an ultrasonic welding head, where the ultrasonic wave generates The output end of the device 5 is connected to the transducer 51, and the transducer 51 is connected to the ultrasonic welding head through the horn 52. When in use, the ultrasonic generator 5 transmits a signal to the transducer 51, and the transducer 51 controls the action of the ultrasonic welding head through the horn 52, thereby realizing the welding operation of the parts to be welded. By applying the above-mentioned ultrasonic welding head, it can be ensured that The smoothness of the welding process and the welding quality of the finished product, and to prevent equipment damage during the welding process.

Figure 1 shows a schematic structural diagram of the ultrasonic welding head provided in this embodiment. Figure 2 shows a schematic side view of the ultrasonic welding head provided in this embodiment. Figure 3 shows a schematic top view of the ultrasonic welding head provided in this embodiment. As shown in FIGS. 1 to 3 , the ultrasonic welding head includes a connecting part 4 and a welding part. The welding part is connected to the horn 52 through the connecting part 4 . Optionally, a blind hole is provided at one end of the connecting portion 4 away from the welding portion, and an internal thread is provided in the blind hole. The horn 52 is provided with an external thread that matches the internal thread on the connecting portion. The horn 52 and The connection part is threaded, the connection is tight, and it is easy to disassemble and assemble.

The welding part includes a welding head body 1, a welding station 2 and a welding tooth 3. The welding head body 1 includes a first connection surface 11; the welding station 2 includes an oppositely arranged second connection surface 22 and a load-bearing surface 21. The first connection surface 11 and The second connection surfaces 22 are connected, and the area of the second connection surface 22 is smaller than the area of the first connection surface 11 ; the welding teeth 3 are arranged on the bearing surface 21 . Among them, one end surface of the welding head body 1 is connected to the connecting portion 4 . In this embodiment, the welding teeth 3 are installed on the welding head body 1 through the welding station 2, and the area of the second connection surface 22 of the welding station 2 is smaller than the area of the first connection surface 11 of the welding head body 1. This design can A step-like structure is formed between the welding head body 1 and the welding station 2. During welding, the welding station 2 can play a transitional role between the welding head body 1 and the welding teeth 3, so that the welding force does not act directly. on the welding head body 1, thereby preventing the ultrasonic welding head from breaking during the welding process and ensuring the welding quality of the parts to be welded; in addition, since a step-like structure can be formed between the welding head body 1 and the welding station 2, the welding station 2. When processing the welding teeth 3, there is a gap for cutting in or out between the welding head body 1 and the welding station 2, thereby simplifying the processing difficulty and reducing the processing cost.

Figure 4 shows a partial structural diagram of the ultrasonic welding head provided in this embodiment. Figure 5 shows a partial structural diagram of the ultrasonic welding head provided in this embodiment. As shown in Figures 3 to 5, in this embodiment, the first connection surface 11 is a rectangular surface, and the second connection surface 22 is a rectangular surface. Optionally, the first connection surface 11 and the second connection surface 22 are arranged concentrically, which can ensure the balance of the force on the welding head body 1 . In another embodiment, the first connecting surface 11 may be a circular surface, and the second connecting surface 22 may be a polygon such as a triangle, a rectangle, a pentagon, a hexagon, or the like. In yet another embodiment, the second connecting surface 22 may be a circular surface, and the first connecting surface 11 may be a polygon such as a triangle, a rectangle, a pentagon, a hexagon, or the like.

The soldering station 2 is generally a columnar structure or a table-shaped structure. One end surface of the soldering station 2 forms the above-mentioned second connection surface 22 , and the other end surface forms the above-mentioned bearing surface 21 . For example, the welding station 2 may be a cylindrical structure, a prism structure, a truncated cone structure or a prism structure. In one embodiment, the soldering station 2 is a quadrangular prism, one of the two opposite rectangular surfaces of the quadrangular prism forms the above-mentioned second connection surface 22 , and the other forms the above-mentioned bearing surface 21 . In the second embodiment, the soldering station 2 can also be a quadrangular pyramid structure. The larger end surface of the quadrangular pyramid forms the above-mentioned second connection surface 22, and the smaller end surface of the quadrangular pyramid forms the above-mentioned bearing surface 21. Similarly, can achieve the above effects. In the third embodiment, the welding station 2 can be a truncated cone structure. A larger circular surface of the truncated cone structure forms the above-mentioned second connection surface 22, and a smaller circular surface of the truncated cone structure forms the above-mentioned bearing surface 21. The same can be done. achieve the above effects. In the fourth embodiment, the soldering station 2 may be a cylindrical structure, one of the two opposite circular surfaces of the cylindrical structure forms the above-mentioned second connection surface 22, and the other forms the above-mentioned bearing surface 21. Of course, the welding station 2 can also be a triangular prism, a triangular cone, a hexagonal prism, a hexagonal cone, etc., which is not limited in this embodiment.

Optionally, when the welding station 2 has a cylindrical structure or a truncated cone structure, a rounded transition surface is provided between the top surface and the side surface of the welding station 2; when the welding station 2 has a prism structure or a prism structure, a rounded transition surface is provided on the welding station 2. There are rounded transition surfaces between two adjacent side surfaces and between the top surface and the side surfaces. By setting the rounded transition surface, the damage to the parts to be welded during the welding process can be reduced and the quality of the finished product can be ensured.

In order to ensure that when processing the ultrasonic welding head, a sufficient gap for cutting in or out can be formed between the welding head body 1 and the welding station 2, the thickness H ₁ of the welding station 2 ranges from 1.8mm to 2.5mm. For example, the thickness H ₁ of the soldering station 2 =1.9mm, 1.92mm, 2.0mm, 2.1mm, 2.11mm, 2.2mm, 2.3mm or 2.4mm, etc.

The forming process of the ultrasonic welding head is: 1) Process the welding head blank and process a cuboid structure on the side of the welding head blank; 2) Process the middle welding station on the end edge of the cuboid structure in step 1). At this time, The cuboid structure in step 1) forms a stepped structure, which are the welding head body 1 and the middle welding station; 3) Process the welding teeth 3 on the middle welding table, and the welding station 2 is formed between the welding teeth 3 and the welding head body 1 ; 4) Finish processing the first connection surface 11 of the welding head body 1 and the second connection surface 22 of the welding station 2 to meet the preset accuracy requirements.

A first connection surface 11 is provided on at least one side of the welding head body 1 . In this embodiment, the welding head body 1 is provided with two first connection surfaces 11 , and the two first connection surfaces 11 are both provided with a welding station 2 and a welding tooth 3 . When the welding teeth 3 on one of the welding stations 2 are damaged, the welding teeth 3 on the other welding station 2 can be used to continue the operation, thereby extending the service life of the ultrasonic welding head and saving processing costs.

Figure 6 shows a schematic diagram of the dimensions of the welding head body 1, the welding station 2 and the welding teeth 3 in the ultrasonic welding head provided in this embodiment. As shown in FIGS. 4 and 6 , the number of welding teeth 3 is multiple, and the plurality of welding teeth 3 are arranged in an array on the bearing surface 21 . Multiple welding teeth 3 interact with the parts to be welded at the same time to improve welding efficiency and welding quality. Optionally, the plurality of welding teeth 3 form a rectangular array, the length of the rectangular array is L ₂ , the width of the rectangular array is B ₂ , the length of the first connecting surface 11 is L1 , and the width of the first connecting surface 11 is B ₁ , among which, 1.6mm≤L1-L2≤2.4mm, 1.6mm≤B ₁ -B ₂ ≤2.4mm. Optionally, in this embodiment, L ₁ =18.75mm, L ₁ =16.75mm; B ₁ =8mm, B ₂ =6mm. This embodiment does not limit the size of the rectangular array formed by the first connection surface 11, the second connection surface 22 and the plurality of welding teeth 3. It can be customized to the size of the parts to be welded, thereby ensuring the welding quality of the finished product. When ultrasonic welding the welding head, it is necessary to ensure that the center of the welding mark formed on the part to be welded coincides with the center of the second connection surface 22 .

Optionally, the distance between the centers of two adjacent welding teeth 3 is no more than 2 mm, which is beneficial to achieving a strong and stable welding effect. For example, the spacing between two adjacent welding teeth 3 can be 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.1mm, 1.2mm, 1.5mm, 1.6mm, 1.8mm, 2mm . In this embodiment, the distance between two adjacent welding teeth 3 is not limited. It can be any value between 0 and 2 mm. It only needs to be convenient for processing on the premise of ensuring stable welding.

In this embodiment, the number of welding stations 2 is one, and one welding station 2 is provided with a plurality of welding teeth 3 arranged in an array. In other embodiments, the number of welding stations 2 can also be multiple. The plurality of welding stations 2 are arranged in an array on the first connection surface 11. Each welding station 2 is provided with at least one welding tooth 3. In this embodiment For example, the number of welding teeth 3 provided on each welding station 2 is not limited.

Figure 7 shows a schematic structural diagram of the welding tooth 3 provided in this embodiment. As shown in Figures 6 and 7, the welding tooth 3 includes an oppositely arranged and concentric welding plane 31 and a fixed plane 32. The fixed plane 32 is connected to the bearing surface 21. The welding plane 31 is used to contact the parts to be welded. The welding plane The area of 31 is smaller than the area of fixed plane 32. During the welding process, the welding pressure gradually increases. Under the action of the welding teeth 3, the parts to be welded begin to deform. Setting the area of the welding plane 31 to be smaller than the area of the fixed plane 32 can cause the parts to be welded to deform. The speed is slowed down to avoid the sudden thinning of the parts to be welded around the welding teeth 3 and the occurrence of cracks.

In this embodiment, both the welding plane 31 and the fixing plane 32 are circular, and an arc-shaped surface 33 is used for transition between the welding plane 31 and the fixing plane 32 . This design can not only eliminate the protective sheet, saving battery manufacturing costs, but also ensure the stability of ultrasonic welding tension and residue, and has strong applicability. For example, the welding tooth 3 has a truncated hemispherical structure or a truncated cone structure. The arc surface 33 may be a convex arc surface or a concave arc surface. This embodiment is not limited to this as long as the welding teeth 3 have sufficient strength to weld the parts to be welded. It has been verified by simulation and experiments that when the welding tooth 3 has a truncated hemispherical structure, the quality of the welded tab is better.

Optionally, the area of the welding plane 31 is S ₁ and the area of the fixing plane 32 is S ₂ , where 4/(95π)≤S ₁ /S ₂ ≤1/(2π). Among them, the fixed plane 32 has a larger area, which can increase the connection area between the welding teeth 3 and the bearing surface 21 and ensure the stability of the connection; during welding, the welding plane 31 is in direct contact with the parts to be welded, and the area of the welding plane 31 Being smaller can result in greater pressure on the surface area of the parts to be welded that is in contact with the welding plane 31, thereby forming deeper indentations and ensuring welding quality.

Since the welding tooth 3 is a hemispherical structure with a cut top, when processing the welding tooth 3, a hemispherical structure with a diameter D can be processed on the welding station 2 first, and then the top cutting operation is performed on the side of the hemispherical structure away from the welding station 2. , thereby forming a welding plane 31 on this side. Optionally, 1.2mm≤D≤1.9mm, the top cutting depth _H2 is 0.02mm~0.1mm, and the area _S1 of the welding plane 31 ranges from ^0.08mm2 ~ ^0.6mm2 . For example, D=1.82mm, the cutting depth is 0.05mm, and S ₁ =0.28mm ² . When processing the welding teeth 3, first process a hemispherical structure with a diameter D on the welding station 2, and then perform a top cutting operation on the side of the hemispherical structure away from the welding station 2. The dotted hemisphere shown in Figure 7 is The radius of the small hemisphere cut from the above-mentioned hemispherical structure is the cutting depth H ₂ .

The following table exemplarily lists the diameter D, the cutting depth and the area S ₁ of the welding plane 31 of the fixed plane 32 of the welding tooth 3. Of course, the above dimensions of the welding tooth 3 are not limited to the examples in the following table. The operator can Make adjustments according to actual conditions.

In other embodiments, both the welding plane 31 and the fixing plane 32 are polygonal, and the transition surface between the welding plane 31 and the fixing plane 32 includes at least one plane. For example, the welding plane 31 and the fixing plane 32 may be a triangle, a rectangle, a pentagon, a hexagon, etc., which are not limited in this embodiment. In addition, this embodiment does not limit the sizes of the welding plane 31 and the fixing plane 32, and the operator can adjust them according to the actual welding scene.

Claims (16)

1. An ultrasonic welding head, including:

   Welding head body (1), the welding head body (1) includes a first connection surface (11);

   Welding station (2), the welding station (2) includes a second connection surface (22) and a load-bearing surface (21) arranged oppositely, the first connection surface (11) and the second connection surface (22) connected, the area of the second connection surface (22) is smaller than the area of the first connection surface (11);

   Welding teeth (3) are arranged on the bearing surface (21).
2. The ultrasonic welding head according to claim 1, wherein the thickness _H1 of the welding station (2) satisfies: _{1.8mm≤H1≤2.5mm} .
3. The ultrasonic welding head according to claim 1, wherein the number of the welding teeth (3) is multiple, and the plurality of welding teeth (3) are arranged in an array on the bearing surface (21).
4. The ultrasonic welding head according to claim 3, wherein a plurality of the welding teeth (3) form a rectangular array, the length of the rectangular array is L ₂ , the width of the rectangular array is B ₂ , and the third The length of a connecting surface (11) is L ₁ , and the width of the first connecting surface (11) is B ₁ , where 1.6mm≤L ₁ -L ₂ ≤2.4mm, 1.6mm≤B ₁ -B ₂ ≤ 2.4mm.
5. The ultrasonic welding head according to claim 1, wherein the welding tooth (3) includes an oppositely arranged and concentric welding plane (31) and a fixing plane (32), the fixing plane (32) and the load-bearing The welding plane (31) is connected to the welding plane (21), the welding plane (31) is arranged to be in contact with the parts to be welded, and the area of the welding plane (31) is smaller than the area of the fixing plane (32).
6. The ultrasonic welding head according to claim 5, wherein the welding plane (31) and the fixing plane (32) are both circular, and the welding plane (31) and the fixing plane (32) An arc surface (33) is used to transition between them.
7. The ultrasonic welding head according to claim 6, wherein the area of the welding plane (31) is S ₁ and the area of the fixing plane (32) is S ₂ , wherein 4/(95π)≤S ₁ /S ₂ ≤1/(2π).
8. The ultrasonic welding head according to claim 6, wherein the welding tooth (3) has a truncated hemispherical structure, and the diameter D of the fixed plane (32) ranges from 1.2mm to 1.9mm; The top depth H ₂ ranges from 0.02 mm to 0.1 mm, and the area S ₁ of the welding plane (31) ranges from 0.08 mm ² to 0.6 mm ² .
9. The ultrasonic welding head according to claim 5, wherein the welding plane (31) and the fixing plane (32) are both polygonal, and the space between the welding plane (31) and the fixing plane (32) The transition surface includes at least one plane.
10. The ultrasonic welding head according to claim 1, wherein the distance between the centers of two adjacent welding teeth (3) is not greater than 2 mm.
11. The ultrasonic welding head according to claim 1, wherein the welding station (2) has a cylindrical structure or a platform structure.
12. The ultrasonic welding head according to claim 11, wherein the welding station (2) has a cylindrical structure, a prism structure, a truncated cone structure or a prism structure.
13. The ultrasonic welding head according to claim 12, wherein when the welding station (2) has a cylindrical structure or a truncated cone structure, a fillet is provided between the top surface and the side surface of the welding station (2). transition surface;

    When the welding station (2) has a prism structure or a pyramid structure, a rounded transition surface is provided between two adjacent side surfaces and between the top surface and the side surfaces on the welding station (2).
14. The ultrasonic welding head according to claim 1, wherein the number of the welding stations (2) is multiple, and the plurality of welding stations (2) are arranged in an array on the first connection surface (11) On each welding station (2), at least one welding tooth (3) is provided.
15. The ultrasonic welding head according to any one of claims 1-14, wherein the first connection surface (11) is provided on at least one side of the welding head body (1).
16. An ultrasonic welding equipment, including an ultrasonic generator 5, a transducer 51, a horn 52 and an ultrasonic welding head as claimed in any one of claims 1-15, the output end of the ultrasonic generator 5 is connected to The transducer 51 is connected, and the transducer 51 is connected to the ultrasonic welding head through the horn 52 .